Deep well drilling device



L E S S A R P V DEEP WELL DRILLING DEVICE Original Filed Sept. 24, 1945 19%;" Pra 55a Z Patented Feb. 7, 1950 a UNITED STATES PTENTL; orries Victor Prassel, San Antonio, Tex.

Original application September 24, 1945, Serial No. 618,255. Divided and this application c-' tober 18, 1946, Serial No. 704,213

2 Claims.

This invention relates to a deep well drilling device and more particularly to a reaming tool for use on a deep well drill, and is a division of my patent for a Deep well drilling device, issued March 1, 1949, bearing Patent Number 2,463,420.

An object of this invention is to provide an improved drill bit which includes a centrally disposed pilot bit which, after initially preceding the main bit, is adapted to be coupled or clutched to the main bit for operation therewith, and which acts to keep the main bit in a straight path so that the main bit will not be deflected when contacting rock or other hard substances.

Another object of this invention is to provide an improved drill bit having a driven pilot bit and a main bit loose on the drive shaft with clutch means on the pilot bit and main drilling bit engageable in the extended position of the pilot bit relative to the main bit, whereby the pilot bit will be retracted and the main bit disengaged from the drive shaft when the pilot bit engages a rock or other impenetrable substance which would deflect the main drill bit from a straight drilling path.

With the foregoing objects in view, and others which may hereinafter more fully appear. the novel construction, combination and arrangement of parts will be more specifically described and illustrated in the accompanying drawings wherein are shown embodiments of the invention, but it is to be understood that chan es, variations and modifications may be resorted to which fall within the scope of the invention claimed.

In the drawings,

Figure l is a longitudinal section of the drill bit, showing the bits in collapsed or retracted position,

Figure 2 is a fragmentary longitudinal section showing the bits in extended position, and

Figure 3 is a side elevation of the main drill bit.

Figure 4 is a cross-sectional view of the device taken on lines 44 of Figure 1.

Referring to the drawings, the numeral i 5 designates generally a casing section, more specifically described in the above mentioned applica tion, within which a drill bit, generally designated by the numeral 22 is rotatably mounted. The drill bit 22 includes a cylindrical body 23 having a plurality of cutting blades 2% pivotally secured thereto. The body 23 is formed with a central opening 25 longitudinally thereof through which a pilot drill 26 of the conventional spiral type is adapted to loosely and rotatably engage. The

body 23 has extending upwardly therefrom a 2 pipe or sleeve 21 whichis threaded into an annular flange 28 carriedby the upper side of the body 23. Within the confines of the annular flange 28 and extending upwardly from the body 23 annularly arranged clutch teeth 29 are carried by the body 23 forming one clutch element with which the drill bit 22 is adapted to be coupled for rotation thereof.

A drill rod 39 extends axially upwardly from the sleeve or cylindrical member 21, engaging through a bearing 3| carried by the upper end of the sleeve 2.1. A clutch collar-or element 32, having teeth 33 on the lower side thereof, is fixed to the lower end of the drill rod 30, and when the bit 26, fixed on the end of the drill rod 3! is in its lowermost extended and operative position, clutch member 32 is adapted to engage the clutch member formed by the teeth 29 so as to rotate the main drill bit 22 with pilot bit 26. Means. as a turbine, are provided within the casing 15 for rotating the pilot bit 25, as described in my copending application.

Transverse downwardly opening slots ll) are provided in the lower end of the body 23 diametrically thereof and at right angles one to the other for pivotally supporting the main cutting blades or bits 24 therein, and a pin 4| extending through the body 23 and shank of the bit 24 pivotally secures the blades in the slots All. The blades 24 are formed of fiat bodies having the inner edge 42 thereof formed of an obtuse angle, having the sides diverging inwardly. The pilot bit 26 is adapted to slidingly engage the edges 42 of all the blades 24, being centrally disposed relative to all the blades. When the pilot bit 2."; is retracted, the blades are pivoted inwardly to each other and the body 23 with the pilot bit 26 engaging along the upper side 44 of the angle 42 so that the lower cutting edges and outer edges of the main blades 24 are disposed inwardly of the casing I5 and the clutch members are disengaged so that the main bit 22 is not rotated. In the extended or operative position, the pilot bit 26 extends below the main bit 22 and engages the lower side 45 of the angle 42 pressing the main blades 24 outwardly and the clutch members are in engagement for rotating the pilot bit 2?; and main bit 22 in unison.

In the use and operation of this device as the pilot bit 25 is drilling through penetrable substances, it will lead the main bit 22 and the clutch members will be engaged as in Figure 2 for rotating the main bit 22, and when the pilot bit 26 encounters some hard substance as a rock or other hard substance, the main bit 22 will continue to drill downwardly a short distance through the penetrable substance rearwardly of the point of the pilot bit until the clutch teeth 29 and 33 become disengaged, whereupon the pilot drill will continue to rotate free of the main bit until such hard substance is penetrated and broken, thereby saving the main bit 22 from undue abuse and the expense and labor of replacing the main drill bits.

I do not mean to confine myself to the exact details of construction herein disclosed, but claim all variations falling within the purview of the appended claims.

What I claim is:

1. An attachment adapted to be mounted ad- J'acent the lower end of a vertical drill rod of a well drilling device comprising: a cylindrical body having a central bore extending therethrough, a plurality of cutting blades positioned radially of said bore adjacent the lower end thereof and pivotally connected to the body adjacent said bore, a vertical sleeve secured to the upper end of said body in axial alignment with said bore, bearing means secured to the upper end of said sleeve, clutch teeth annularly arranged in the upper surface of said body adjacent said bore and within said sleeve, a pilot bit rotatably mounted above said bore and slidable vertically therein, a drill rod connected to the upper end of said pilot bit, a radial clutch element rigidly secured to the upper end of said pilot bit beneath said bearing means engageable on its upper surface With said bearing means to support said body during the lowering of said attachment in a w l, clutch teeth provided on the under surface of said clutch element engageable with the teeth on said body, to impart rotation to said body when the pilot bit has advanced a distance suflicient to allow for the engagement of said clutch elements.

2. A device as set forth in claim 1, said cutting blades being L-shaped, the vertical legs of said blades being pivotally connected at their upper ends adjacent said bore, the horizontal legs of said blades extending radially outwardly from said bore, said pilot bit engageable with said cutting blades to force the latter outwardly from the bore.

VICTOR PRASSEL.

REFERENCES CITED The following references are of record in the tile of this patent:

UNITED STATES PATENTS Number Name Date 1,142,460 Roby June 8, 1915 1,835,108 Arthur et al. Dec. 8, 1931 2,054,255 Howard Sept. 15, 1936 2,064,255 Garfield Dec. 15, 1936 2,323,027 Gerstenkorn June 29, 1943 2,463,420 Prassel Mar. 1, 1949 2,472,710 Koeln June '7, 1949 

